Improvement in chucks for metal drills



T. HoPPE. V cHUcKs FOR METAlL-DRILLS. l No. 171,383. Patented Dec.21,1875.l

UNITED STATES `TEEoDoRE HorPE, oE LAWRENCE, MASSACHUSETTS.

IMPROVEMENT IN CHUCKS FOR ME'l-'AL DRILLS.

Speciication forming part of Letters Patent No. 171,383, dated December2l, 1875; application tiled November 29, 1875.

. of Massachusetts, have invented an Improve- `ment inlSelf-GenteringChucks, of which the p following is a full, cle'ar, and exactdescription, reference .being had to the accompanying drawings makingpartof this specification, in which- Figure l is .a perspective view ot'a chuck constructed in accordance with my invention. Fig. 2 isalongitudinal vertical section through the center ofthe same. Fig. 3 isa transverse vertical section through the same on the line a: x of Fig.2. Fig-4 is a perspective view of one of the jaws detached. Fig. 5 is aperspective view of the spindle.

This invention consists in a chuck in which the jaws are each providednear the front end with an open slot, in which lits a flange projectingfromthe inside of the outer end ofthe shell or exterior casing, thejaws,'which are wedge-shaped and ot dovetail form, fitting intocorrespondiugly-shaped inclined grooves in the interior of the stock orspindle, over which is screwed the outer casing, the turning of whichupon the spindle causes the jaws to or spindle, the front end ot' lwhichis enlarged and provided with a screwthread, over which is turned thecylindrical outer shell or' casing B, provided on its interior with acorresponding screw-thread, and on its exterior with ribs or projectionsb which al'ord a lirm grasp for the hand. The enlarged portion 0f thespindle A is hollow, and within this portion are formed three radialgrooves, c, each ot which is inclined, and is of dovetail form at theback or inner side, as" seen in Fig. 3. Within these grooves are fittedthe sliding jaws d, each of which is made in the form of a wedge, asseen .in Figs. 2 and 4:, and is of dovetail form at its rear, so as tocorrespond in shape to that fof the inner portion ot' the groove c inwhich it slides, the inner` faces ot' the jaws being made angular incross-section, and the holdin g-edges being atall times parallel to eachother and to the longitudinal axis ofthe chuck. Near the front of eachof the jaws d, and at the back thereof, is an open slote,` :and intothese slots extends a liange or iiat ring, j', projecting from the innerside ot the outer end of jaws are made to slide'in the inclined groovesc, which thuscause the jaws to move in a plane at right angles to theaxis ot' the chuck toward or from a common center in order to grasp orrelease a drill or other article placed between them. By making the jawsd, and

the grooves in which they 'slide,`of dovetail form, the jaws areprevented from dropping down out of their proper positions, vas wouldotherwise be liable to occur.

The above-described chuck, which I prefer to make of steel, possessesthe advantage ot extreme ,simplicity of construction, havin g but fewparts, and no springs or pivot-s which are objectionable on account oftheir liability t0 break or get out ot' order. Furthermore, it can bemanufactured at a small cost, and is durable and eltective. j

`What I claim as my invention, and desire to secure by Letters Patent,is-

'Iheouter casing B, with its angef, in combination with the dovetailjaws d', provided with slots e, and fitting into inclined dovetailgrooves in the spindle A, all constructed and arranged to operatesubstantiallyr in the manner and for the purpose set forth.

vWitness my hand this 26th day ot' November,-A. D. 1875.

THEODOBE HOPPE.

In presence of- JOHN C. SANBOEN, E. W. CoLeoaD.

PATENT (')EEIGEt

